package com.chen.reggie.filter;


import com.alibaba.fastjson.JSON;
import com.chen.reggie.common.BaseContext;
import com.chen.reggie.common.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */

@WebFilter(filterName = "loginCheckFiler",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {


        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response  = (HttpServletResponse) servletResponse;

        // 1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求:{}",requestURI);

        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
                "/doc.html",
                "webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };

        // 2、判断本次请求是否需要处理(该次访问是否处于登录状态)
        // 3、如果不需要处理，直接放行
        if(check(urls,requestURI)){
            log.info("放行对应的请求:{}",requestURI);
            filterChain.doFilter(request, response);
            return;
        }
        // 4-1、判断登录状态(session中含有employee的登录信息)，如果已经登录，则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登陆,用户的id为:{}",request.getSession().getAttribute("employee"));
            Long empID = (Long) request.getSession().getAttribute("employee");

            BaseContext.setCurrentId(empID);


            filterChain.doFilter(request, response);
            return;
        }
        // 4-2、判断登录状态(session中含有user的登录信息)，如果已经登录，则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登陆,用户的id为:{}",request.getSession().getAttribute("user"));
            Long userId = (Long) request.getSession().getAttribute("user");

            BaseContext.setCurrentId(userId);


            filterChain.doFilter(request, response);
            return;
        }

        // 5、如果未登录，则返回未登录的结果
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(Result.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配是否放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            if(PATH_MATCHER.match(url, requestURI)){
                return true;
            }
        }
        return false;
    }
}
